What is a mini power plant

A history of what mini power plants are, their areas of application and advice on purchase and operation.

Reasons and objectives for acquiring mini power plants

In many cases, an autonomous power source is required. For example, it can be a country house — after all, it's no secret that power outages in rural areas happen quite often.

Another case is construction, as it is not always possible to connect to the power grid and there are many different mechanisms that require electricity on a construction site. Even outdoor recreation is more fun and convenient if you have a portable electric generator: on the bank of the river you can organize a disco, lighting or even a performance of a popular rock band.

Portable power generators are widely used in commerce, manufacturing of perishable products and medical institutions.

Types of mini power plants

In the event that a low-power source of energy is required, gasoline generators manufactured for domestic use are quite suitable. If a sufficiently powerful and reliable backup power source is required, then a diesel generator is more suitable.

How to determine the power of a mini power plant

When buying a mini power plant, you must first determine what power is needed, what devices, tools and mechanisms you will connect.

By the nature of the load, all electrical appliances are divided into active and inductive. Active users include lighting, electric stoves, electric fireplaces, kettles, etc. Such devices, as it is easy to see, convert electricity into heat.

Inductive loads include those devices that have electric motors. These are refrigerators, pumps, compressors, saws, drills and many other power tools and accessories. In this case, the transformation of electrical energy into mechanical energy occurs.

To determine the required power of the generator in the case of connecting active loads, you just need to determine the total power of all devices that can be turned on at the same time. Add another 15 ... 20 percent to the resulting power, so to speak, «safety margin». This will be the required power of the generator.

Electrical equipment of the inductive type differs in that when it is turned on, it creates large inrush currents, therefore the total power must be increased by 2.5 ... 3 times (250 ... 300 percent). With such a power reserve, the operability of the generator will be properly ensured: there will be no overloads and frequent shutdowns of the protection.

If you plan to use a generator for a country house, then, as practice shows, the power of 1.5 ... 2 kilowatts turns out to be enough: all electrical equipment consists of a few light bulbs, a TV and sometimes an old refrigerator.

In order to prevent frequent power outages from causing inconvenience to the owners of large country cottages, it is necessary to purchase a generator with a power of 10 ... 30 kilowatts.

A generator capacity of no more than 6 kilowatts will be quite sufficient for construction work. In this version, it will be possible to use a concrete mixer, grinder, drill, perforator.

How to choose a diesel power plant

If the load consumed by your equipment is 10 kilowatts or more, then in case of prolonged interruptions of the centralized power supply, it is better to use diesel generators for the normal operation of the electrical equipment. In long-term use, they are more reliable than independent gasoline power supplies.

It should be noted that it is simply harmful for a diesel engine to idle for a long time. In order to avoid the harmful consequences of working at partial loads, for prevention it is necessary to organize the work in such a way that every 100 hours of work of the diesel engine to have at least 2 hours with 100% load. You should also beware of overloading, the signs of which are: power failure, significant reduction in power, overheating and heavy soot.

How to choose a gasoline engine power plant

If you decide to buy a mini-power plant with an imported gasoline engine, then the main attention should be paid to the design of the engine, which depends on its resource and, therefore, the durability of the entire installation.

Engines with side valves and an aluminum cylinder block have a low price and a correspondingly short service life, which, as a rule, does not exceed 500 hours. Engines with cast-iron cylinder liners and side-mounted valves have a longer life - about 1500 hours.

Industrial engines have cast iron liners, cylinder valves and oil supply to pressurized parts. Such engines are characterized by a low noise level, have low fuel consumption, and their service life is at least 3000 hours, which is almost the same as that of diesel engines.

How to choose the type of generator of mini power plants

Both synchronous and asynchronous generators are used in mini power plants. Let's take a look at their features and applications.

For emergency power supply of most sites, such as offices, refrigeration equipment, country houses and cottages, construction sites, synchronous generators are perfectly suitable. They are less accurate, but they cope without problems with the power supply of electric motors and power tools, whose reactive power reaches 65% of the nominal one.

More precisely, the voltage in the network is maintained by asynchronous generators, which is why they are recommended to be used in the case of using equipment that is sensitive to voltage spikes. Most often, these are medical equipment, domestic heating boilers with an electronic control unit and other electronic devices.It is also possible to connect electric motors and power tools with reactive power not more than 30% of the nominal to such generators.

Automation of mini power plants

The control and monitoring unit is designed to control the operation of the mini power plant. With its help, such tasks as monitoring the parameters of the power network, a programmable system for automatic start-up, protecting users from increasing or decreasing voltage are solved. If the mains voltage goes out of the permissible range, the control unit ensures automatic start of the generator.

The main functions of the control and monitoring unit

In the event that the voltage level in the main power network exceeds the tolerance limits, the control unit must start the power plant in a timely manner. These parameters are programmed by the user himself. This does not require the services of a service center: everything is described in sufficient detail in the user manual.

When restoring the parameters of the main power network, the control unit must connect the user to it. In this case, the operation of the mini-power plant must be stopped.

In addition, the control unit must perform a generator test during periodic inspections.

The control unit also contains a timer with which you can program the start time, the time to wait before starting, the time between start attempts, the time when the power plant is stopped and the number of failed starts. This data is stored in non-volatile memory and is always available for review and analysis.

The control unit executes display parameters electrical network, different modes of operation and failures.

Even in the absence of people in the house, the programmable system of the control unit ensures complete independence when the main power is turned off. Therefore, equipment such as a refrigerator will work without interruption.

The number of phases of the mini-power plant

When buying, you should pay special attention to the number of phases in the power plant. If you have single-phase electrical wiring and devices, then the power plant must also be purchased single-phase at 220V.

For industrial use, as well as for large cottages with three-phase wiring, you need to purchase a three-phase generator for 380 volts (this is the voltage between two phases) and between zero and phase of 220V. Three-phase users will receive three-phase and single-phase 220V.

In order for the three-phase generator to work normally, the load on the phases must be distributed evenly. This condition will be met if the power difference between the phases is not more than 25 percent.

Currently on sale there is a large assortment of stations that differ not only in price, but also have different purposes. Therefore, when buying a unit, you should think about all the options for its use: the main or backup, it will be located indoors or outdoors, a mobile or stationary option, regardless of whether it is necessary to automatically start in the event of a power failure in a centralized electrical network.

After analyzing all the possibilities of the blocks, choose the most suitable one for you, and then you will not have to pay more for the options you do not need.

Installation and warranty service

The range of mini power plants on sale today is quite wide, and it will not be difficult to choose the one that suits you best. But even if the power plant is manufactured by a well-known reputable company, this does not give full guarantees for its reliable operation.

Such work will be provided in the event that the equipment is purchased from a company that will deliver it to the customer within the terms specified in the contract and without damage, and the connection will be carried out by qualified specialists.

In case of even minor damage, the company's specialists will carry out a quick repair. If the company you contacted provides such services, then your power plant will work reliably for a long time.